Rope climbing devices

ABSTRACT

A rope climbing device which includes two drum members about which a rope is wound, the drums having a number of circular grooves on the drum circumference, in which the rope sits. The axes of the drums are tilted through such an angle relative to each other that one end of a groove on one drum, viewed radially, overlaps a groove of the other drum and at the other end overlaps the next adjacent groove of the other drum.

United States atent Mattinson [451 Aug. 1, 1972 [54] ROPE CLIMBING DEVICES 232,426 8/1944 Switzerland 254/ 175.7

[72] Inventor: Frederick Mattinson, Andover, En-

l d Primary Examiner-Even C. Blunk 73 A M Th d Assistant Examiner-J. Kenneth Silverman sslgnee ggggh gz g mute Att0rneyWi1liam Anthony Drucker [22] Filed: July 10, 1970 [57] ABSTRACT pp No 53,933 A rope climbing device which includes two drum members about which a rope is wound, the drums hav- 3() F i A li p i i Data ing a number of circular grooves on the drFm circumference, in which the rope sits. The axes o the drums July 1969 Great Bmam "36477/69 are tilted through such an angle relative to each other 52 us. Cl ..2s4/17s.7 that end a groove drum viewed radi 51 Int. Cl. ..B66d 1/76 any, overlaps a of the ("her drum and the 58 Field of Search ..254/175.7 other end overlaps the next adjacent groove of the other drum.

[56] References Cited 2 Claims, 10 Drawing Figures I i 31 Q I PATENTEDAUSI I972 SHEET 6 0F 6 ROPE CLIMBING DEVICES one end of the helix and added to the other end of the.

helix, the net result being a movement of the helix from one end of the drum to the other, whilst the drum is rotating.

The helical configuration of the rope can be prevented from moving along the drum by having circular grooves on the drum circumference.

A means must then be available to transfer the rope from one circular groove to the next whilst maintaining the rope helix...

In the past, transfer of the rope has been known to be accomplished at the expense of rope life, because known methods involve side loading on the rope to achieve transfer and a scrubbing action takes place between rope and drum surface due to this side load mg.

The proposal according the present invention is that the wire rope can be transferred from one groove to the next without using a method that requires 'the rope to be forced into position.

According .to the present invention there is provided a rope climbing device including first and second drum members about which a rope is arranged to be wound, at least the first one of the drums being provided with a number of circular grooves, the first and second drums being mounted for rotation in such positions that the central plane of each groove is at an angle to a plane through the second of the drums, at right angles to its axis, such angle being selected so that one or more of the grooves of the first drum member has a first part aligned with an associated rope position leaving the second drum and another part approximately 180 offset from the first part aligned with an associated rope position approaching the second drum.

Advantageously with the correct design of grooves in the first drum and with the drum axis normal to the rope helix, the rope can be transferred smoothly and without damage.

The device is particularly for use in scaffolding hoists, cradles and work platforms for carrying workmen.

Constructional forms of the present invention will now be described by way of example, with reference to the accompanying drawings, wherein:

FIG. 1 is a perspective view of part of a rope climbing device made in accordance with the invention;

FIG. 2 is a view thereof in the direction of the arrow 2 on FIG. 1;

FIG. 3 is a view thereof in the direction of the arrow 3 on FIG. 1;

FIG. 4 is an axial view of a modified form of device;

FIG. 5 is a view in the directionof the arrow 5 on 7 FIG. 4;

FIG. 6 is a front elevational view of a rope climbing device made in accordance with the invention;

FIG. 7 is a view of the rope climbing device in the direction of the arrow 7 in FIG. 6,

FIG. 8 is a plan view of the direction of arrow 8 in FIG. 7.

FIG. 9 is an enlarged view of parts of the safety device shown in FIG. 6; and

FIG. 10 is a side view (corresponding to FIG. 7) of the parts shown in FIG. 9.

In the device shown in FIGS. 1 to 3 a first rope guide means is in the form of a drum 12 formed with two circular grooves 13, 14 to receive rope 15. A second rope guide means is in the form of a drum 16 having two circular grooves l7, 18. The central planes of the grooves 13, 14 (B3, B4 and B1, B2 respectively) FIG. 3 are parallel to each other. Similarly the central planes of the grooves 17, 18 (A3, A4 and Al, A2 respectively) are parallel to each other. The axes of the drums are in planes 20, 21 parallel to each other as viewed in FIG. 2.

As viewed in radial view with the guide means 16 superimposed on the first guide means 12 as shown in FIG. 3 the axes are tilted at an angle 22 to each other, this being effected geometrically by tilting the drum 12 about a point Bl at the bottom of groove 14, which coincides with point A2 at the bottom of groove 18 on drum 16, whereby groove 17 as seen in that view overlaps groove 13 at one end and groove 14 at its other end.

The path of rope 15 from the drum 12 to drum 16 and back to the drum 12 forms a helix (as in FIG. 1) but eliminates any tendency for the helix to feed to one end of the drum or the other.

The flank angles of the grooves in the drum 12 and drum 16 are suitably designed according to different diameters and different sizes of ropes to prevent undue scrubbing of the rope 15 with a consequent reduction in its life. i

The system may be varied by having drum 12 with a slight taper over-all or part of its length, and the drum 16 may be separated into single groove drums and spaced on an are around the drum l2 axis instead of being on a common axis.

Points A to A also respectively indicate the center of the rope at points where the rope enters and leaves drum l6.

Points B to 13., also respectively indicate the center of the rope at points where the rope enters and leaves drum 12. The location of these points, at the pitch radius of the drums, will depend on the ratio of drum diameters and the distance between the drums. A line drawn normal to the rope longitudinal center line at these points will pass through the respective drum centers.

The drum 12 is tilted about point B, (as seen in FIG. 3) through the angle 22 such that a central plane 26 joining points B B is parallel to the central plane of groove 17. Also the central plane 26 passes through points A A Thus the drum 12 is tilted about a line B1, A2 tangential to the grooves 14, 18 i.e. about a line corresponding to the path of the rope from groove 14 to groove 18.

' The angle 22 will depend on the center distance between drums, the relative diameter of the drums and the transverse pitch of the grooves.

The system may be varied by utilizing separate single grooved drums on a common axis. Also the transfer of the rope may be accomplished by guide pulleys spaced around drum 12, with their centers on an arc radial to the drum axis instead of being on a common axis.

In the modification shown in FIGS. 4 and 5 the second drum 16 in the superimposed view of FIG. 5 is tilted about the axis 28 so that again each of the grooves in drum l6 overlaps next adjacent grooves of the drum 12.

Referring now more particularly to FIGS. 6 to 8 there is shown a rope climbing device comprising an electric motor 30 which is arranged to drive a grooved drum 31 for example of 7 inch pitch diameter. The drum 31 is associated with a freely rotatable drum 32 for example of a 4% inch pitch diameter, which is tilted relative to drum 31 as hereinbefore described with reference to drums 12,16 in FIGS. 1 to 3. A hoist rope 33 is provided around the drums 31,32 and emerges from the rope climbing device through a safety brake arrangement 34. A safety rope 35 is also provided, which rope passes through the safety brake arrangement 34.

The electric motor 30 receives its operating current from a suitable electrical supply (not shown) and in operation drives an output shaft 36 thereof which is coupled to a worm reduction gear generally indicated by the reference numeral 37. An output shaft 38 of the worm reduction gear 37 drives a coupling member 41 which carries a nut 41A located on a threaded part of a shaft 39. The coupling member allows for axial movement of the nut on the shaft. The shaft is rotatable on bearings 40. A ratchet wheel 42 is freely rotatable on the shaft 39. Positioned on the shaft 39 against opposite sides of the ratchet wheel 42 are friction discs 43, 44 such as Ferrodo (Registered Trademark). These discs are freely rotatable. Pressure plates 45, 46 are located against the discs 43, 44 respectively. Plate 45 is fixed to shaft 39 and plate 46 is fixed to coupling 41. A ratchet pawl 50, clearly shown in FIG. 7, engages the ratchet wheel 42 when the motor 30 is switched off and prevents the rope climbing device from moving relative to the hoist rope 33. When it is required to move the climbing device downwardly of the hoist rope 33 the motor is reversed, releasing pressure on the discs 43, 44 which then slip relative to the fixed ratchet wheel 42. This ratchet and friction disc arrangement is substantially the same as is described in US. Pat. No. 2,756,947 (Arnold) (see especially FIG. 6 thereof).

As the climbing device moves down the rope the rotation of the pinion 51 on shaft 39 is such as to increase the pressure on the discs 43, 44 thereby effectively acting as a brake and reducing the downward movement of the climbing device. However, the motor 30 still operates to relieve the pressure on the discs 43,44. Therefore between the two actions a controlled lowering of the climbing device on the hoist rope is obtained. When hoisting the construction ensures that when drive is put into neutral the load will drive back through the shaft 39 tightening the nut 42A on the screw thread which in turn brings the brake friction plates 45, 46 into contact with the discs 43, 44 to engage the ratchet wheel 42, the load being held by the ratchet. The brake is over ridden when lowering as the drive tends to unscrew the thread releasing pressure from the clutch friction faces.

Returning now to describe an upward movement of the rope climbing device, the shaft 39 drives a helical pinion 51 and a final helical gear drive wheel 52. The gear wheel 52 is provided with a shaft 53, rotatable in bearings 54, to which is fixedly joumalled drum 31.

The drum 32 is mounted above the drum 31, in FIGS. 6, 7 and rotates freely on bearings 55.

As drum 31 rotates the friction of the hoist rope 33 upon drum 32 causes it to rotate and the rope climbing device moves relative to the hoist rope. The effect of the drums 31, 32 as previously mentioned is, to maintain the hoist rope in a fixed position relative to the longitudinal axis of the drum 31 and to minimize or eliminate the effect 0 scrubbing" on the rope thereby increasing the length of the life of the rope.

The bearings 40, 54, 55 are retained in upright body members 60, 61. A further portion 62 of the body of the rope climbing device serves to house the worm reduction gear 37. Body portion 62 is detachably connected to body member 61 so that the motor 30 and worm reduction gear 37 can be removed as a single unit from the rope climbing device thereby simplifying maintenance and servicing. Removal of the motor and reduction gear is further enhanced by the sleeve gear coupling 41. The body portions 60, 61, 62 are preferably formed of a cast aluminium alloy.

The safety brake arrangement 34 comprises two plates 70, 71 pivotally mounted on a shaft 72 having fixedly joumalled thereon a gear 73. The shaft 72 is carried in bearings 72A in the housing of the device. The plates 70, 71 are provided with an interconnecting pin member 74 which also projects from plate 72 to be retained by a U-shaped portion 75 of a brake shoe 76. The brake shoe is spring loaded by a spring 83 and retained within a shoe housing 77.

The safety brake arrangement is further provided with a pulley member 78 which engages with the hoist rope 33 and which rotates about an axle 78A fixed relative to plate 70. The pulley 78 is provided with two pawls 79 which are engageable with stops 80 on a disc 81 to drive a pinion 82 and hence the gear wheel 73.

Only one pawl 79 is shown and the other is exactly the same, the two pawls being offset 1 80 to each other.

In normal operation of the safety brake arrangement 34 the pulley 78, due to the tautness of hoist rope 33, takes up a position which pivots plates 70, 71 about shaft 72 causing shoe 76 to be pushed against spring 83 out of contact with the safety rope 35 whereupon the rope climbing device can be moved freely up and down the hoist rope.

Should the hoist rope 33 break, the pulley 78 is no longer held in position to allow free movement of the climbing device due to the slackness in the hoist rope, and hence the spring 83 forces the shoe 76 towards the safety rope 35.

The shoe 76, as shown in FIG, 7, is tapered and the tapered surface thereof is engageable with two rollers 76A, 76B having their axes fixed relative to the shoe housing 77. Therefore as the shoe 76 moves by the force of spring 83 the two rollers ensure substantially frictionless movement of the shoe and movement thereof towards the safety rope 35.

Should a fault occur in the transmission from the motor to the drum 31, for example, the climbing device may begin to fall rapidly. In this case the speed of rotation of the pulley 78, positioned to allow free move ment of the climbing device as described, begins to in crease whereupon the pawls 79 are gradually moved into engagement with stops 80 on disc 81 by centrifugal force. As disc 81 rotates pinion 82 drives gear 73 which rotates shaft 72 upon which plates 70, 71 are pivotally mounted. Shaft 72, in the region of plates 70, 71 is provided with flat shaped portions 84, clearly seen in FIG. 7 and FIG. 10. The plates 70, 71 are each provided with a slot 85, large enough to receive the flat shaped portions of the shaft 72 edgewise.

Therefore as shaft 72 rotates the portions 84 thereof become edgewise on to the slot 85. The spring 83 then acts via the brake shoe 76 to move plates 70, 71 until flat portions 84 are retained within the slots 85. In moving plates 70, 71 the latter act as a lever to cause the pin member 74 to force the shoe 76 into engagement with the safety rope 35 and bring the climbing device to a halt.

Generally with such climbing devices it is necessary to provide a tail end load, i.e. a load on the lower end of the hoist rope beneath the climbing device.

In the above described embodiment of a rope climbing device the tail end load is simulated by the application of a force upon the hoist rope in the region of the drum 31. This force is applied, as can be seen from FIG. 7, by a number of pressure rollers 90 which are carried by one or more shoes 92 and are spring loaded against the drum by springs 91 either individually or as a complete assembly. The motor 30 can be switched on for a short burst to enable the leading end of the rope to pass between the rollers and the drum 31.

The drums 31, 32 are preferably made of cast nodular iron having machined grooves of 13/32 inch diameter. Furthermore the bearings are of ball or roller bearings fitted with integral seals. The bearings may be provided with mechanical seals provided provision is made for lubrication.

The device achieves its lifting capacity by virtue of the pre-load at the trailing end of the rope, which induces a grip on the drum 31 and by having a suitable number of coils of rope on the drum of the device will exert a force at the other end of the rope equivalent to the pre-load multiplied by e where e=2. 178, u=Coeff. of friction between rope and drum and e= total angle of lap of rope around rum in radians.

The main advantages of using a device of this type are that, since it does not have to store the wire rope as it climbs up it the safe working load remains constant; it can be designed as a more compact unit, the operating height of a unit depends only upon the length of wire rope that it is climbing. For a given capacity of device the absence of a rope storage drum reduces the weight of the unit and consequently it is more portable.

Iclaim: 1. A rope climbing means comprising a support body, drum means about which the hoist rope to be climbed can be wound so that the support body moves iv ted on th at sh e ortion and e a in the Bralte shoe, said lever vi ng a slot at its rii1oec part which can engage over the flat portion in one rotary position, the flat portion holding the lever depressed and thereby holding the brake shoe disengaged from the safety rope until the slot moves over the flat portion whereupon the lever moves up to enable the brake shoe to engage the safety rope should the rope climbing means inadvertently descend the hoist rope, said lever also pivoting on the flat portion should the hoist rope break to enable the brake shoe to engage the safety rope.

2. A hoist rope climbing device comprising a support body, first and second grooved drums about which a rope to be climbed can be wound, the drums being mounted for rotation on said body in such positions that their axes are at an angle to each other such that at least one groove of the first drum member has a first part aligned with an associated rope position leaving the second drum and another part approximately offset from the first part aligned with an associated rope position approaching the second drum, a series of rollers, spring means urging said rollers to hold the rope against the first drum, gear means for driving the first drum, means for releasing drive from the gear means to permit descent of the climbing device, and a safety device comprising a brake shoe, spring means to urge the brake shoe against av safety rope a brake shoe control member which normally engages the brake shoe to hold it in disengaged position, means to permit pivotal movement of said control member on breakage of the hoist rope to allow the brake shoe to engage the safety rope, and means tov allow vertical movement of said control member if the climbing device inadvertently descends the hoist rope thereby also permitting the brake shoe to engage the safety rope. 

1. A rope climbing means comprising a support body, drum means about which the hoist rope to be climbed can be wound so that the support body moves up the rope when the drum is rotated, a brake shoe device for engaging a safety rope, said device including a brake shoe, spring means urging the brake shoe to engage with a safety rope, a pulley engaging the hoist rope, centrifugally acting means carried by the pulley, gear means engageable by the centrifugally acting means on rotation of the pulley, a shaft driven by the gear means and having a flat shaped portion, a lever pivoted on the flat shaped portion and engaging the brake shoe, said lever having a slot at its pivoted part which can engage over the flat portion in one rotary position, the flat portion holding the lever depressed and thereby holding the brake shoe disengaged from the safety rope until the slot moves over the flat portion whereupon the lever moves up to enable the brake shoe to engage the safety rope should the rope climbing means inadvertently descend the hoist rope, said lever also pivoting on the flat portion should the hoist rope break to enable the brake shoe to engage the safety rope.
 2. A hoist rope climbing device comprising a support body, first and second grooved drums about which a rope to be climbed can be wound, the drums being mounted for rotation on said body in such positions that their axes are at an angle to each other such that at least one groove of the first drum member has a first part aligned with an associated rope position leaving the second drum and another part approximately 180* offset from the first part aligned with an associated rope position approaching the second drum, a series of rollers, spring means urging said rollers to hold the rope against the first drum, gear means for driving the first drum, means for releasing drive from the gear means to permit descent of the climbing device, and a safety device comprising a brake shoe, spring means to urge the brake shoe against a safety rope a brake shoe control member which normally engages the brake shoe to hold it in disengaged position, means to permit pivotal movement of said control member on breakage of the hoist rope to allow the brake shoe to engage the safety rope, and means to allow vertical movement of said control member if the climbing device inadvertently descends the hoist rope thereby also permitting the brake shoe to engage the safety rope. 